油井用硫酸钡锶垢抑制剂XY-1性能影响因素研究

油田开发过程中,由于温度、压力变化,水的化学不相容性等原因,油井出现结垢问题是很普遍的问题,尤其是硫酸钡锶垢,难溶难除,严重影响油井产量和油田效益。本文根据油田硫酸盐垢的防治现状,以顺丁烯二酸酐(MA)、甲基丙烯酸(α-MAA)、丙烯酸甲酯(MAC)为单体,过硫酸铵(APS)为引发剂,水为溶剂制得抑制剂。研究了合成条件对抑制剂性能的影响,评价了其对硫酸钡,硫酸锶垢的防垢性能。实验表明,顺丁烯二酸酐、甲基丙烯酸和丙烯酸甲酯摩尔比为2∶1∶0.5,引发剂过硫酸铵质量为单体重12%,70℃下反应5 h合成的共聚物抑制剂加量在24 mg/L时的防垢率可以达到96%以上。

Research of the effects on the performence of scale inhibitor XY-1 for barium/strontium sulfate in wells

During the oilfields production,it is very common that scale exists in the well for temperature,pressure changing and chemical incompatibility.Especially barium and strontium scaling are difficult to remove.Thus,it affects seriously production and economic of the oilfields.According to the current situation of the sulfates scale inhibitor on the oilfield,a kind of ternary copolymer as a scale inhibitor was designed.The copolymer inhibitor was synthesized from maleic anhydride(MA),vinyllacetate(α-MAA) and methacrylate(MAC) through free radical polymerization in aqueous solution with the ammonium persulfate as initiator.The effects of synthetic conditions on the antiscaling properties were analyzed and the antiscaling properties of the inhibitor on the BaSO4 scale and SrSO4 scale were evaluated.The results showed that the optimum synthetic conditions were followed:molar ratio of MA,α-MAA and MAC 2 ∶1 ∶0.5,mass percentage of initiator 12%(based on the total mass of reactants),mass ratio of monomers to water 1 ∶2,reaction temperature 70 ℃,reaction time 7 h.In this way,scale-inhibiting efficiency of the initiator was up to 96% with the number of the initiator 24 mg/L.